Think humans are the only noisy sleepers? Think again.

There are countless anecdotal reports from zookeepers and pet owners about how their animals snuffle, wheeze and snort in their sleep.

While many species may make noise during slumber, that doesn't mean these animals are necessarily snoring.

Mammals are the only animals that can snore because of how their throats are formed.

Snoring occurs when the flow of air through the nose and mouth is obstructed, and it’s most common when people are sleeping on their backs because the lower jaw often drops open.

Airflow can be blocked by a variety of factors that result in snoring, including the tongue, large tonsils or even a stuffy nose.

So even though some of the animal sleepers we've rounded up aren't actually snoring, there's no denying they'd be noisy bedmates. (Note: For best effect, you'll need to adjust the volume to hear each snorer's performance.)

Dog's Daffy Duck impression

Dozing duck

Dormouse that can't be disturbed

Big sounds from a tiny hedgehog

The loudest hummingbird you'll ever hear

Hibernating bear

One chatty bunny

Puppy snuffles in his sleep

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